Method and a device for compensating weighing faults in feeders for carding machines



July 13, 1954 Q SANDELIN 2,683,289

METHOD AND A DEVICE FOR CDMPENSATING WEIGHING FAULTS IN FEEDERS FOR CARDING MACHINES Filed D80. 15, 1948 Patented July 13, 1954 METHOD AND A DEVICE FOR COMPENSAT- ING WEIGHING FAULTS IN FEEDERS FOR CARDING MACHINES Olle Evald Sandelin, Malmo, Sweden Application December 15, 1948, Serial No. 65,352

Claims priority, application Sweden January 23, 1948 6 Claims. 1

Certain kinds of carding materials are usually fed to the carding machine proper with the aid of a feeding apparatus weighing out successive batches of carding material in a scale which automatically empties the Weighed-out batches in succession on to a feeding cloth conveying the material to the carding machine and moving at a determined speed in relation to the carding means of the machine, the successive batches from the scale being packed together to a continuous layer on the lattice by a plate reciproeating longitudinally of the lattice. This carding material is not weighed out as exact as necessary by the known feeders, since there constantly occur relatively great weighing faults which may often amount to per cent and more, particularly when these faults are systematic ones of short or long duration. On account of these incorrect weighing operations irregularities naturally occur in the web produced by the carding machine and the said irregularities will be apparent in the spun yarn also. These irregularities involve of course an inferior quality of the finished product and they also greatly disturb the manufacture as breakages of the thread will occur from the carding machine and up to the finished product. Therefore, efforts have been made to improve the weighing out of the carding material, but hitherto these efforts have generally been limited to measures for attaining a more suitable supply of carding material to the scale, a greater sensitivity of the weighing machine and for providing control devices which direct the attention of the workers to great weighing faults, so that they may intervene as soon as possible and remove the cause of the fault. However, by these measures a complete compensation of the weighing faults of the feeding apparatus has by no means been realized. It has also been proposed to reciprocate the plate packing together the batches from the scale on the feeding lattice to a continuous layer, at a speed that varies proportionally to the real amount of carding material weighed out in the scale, but in this manner it is not possible to attain any compensation of series of carding material batches having underweight and overweight.

The principal object of the invention is to provide a method and a device for compensating the weighing faults in such feeders for carding machines in such a way that a complete compensation of the weighing faults is obtained both theoretically and practically by means of a relatively simple device suitable for practical use.

Other objects and advantages of the invention will be apparent from the following description of an embodiment shown diagrammatically in the accompanying drawing as an illustrative example only.

In the drawing part of a feeding apparatus I for a wool carding machine (not shown) is illustrated. The feeding apparatus I in general is of a known conventional construction and has a feeding lattice 2 passing over two return pulleys 3 and 4 and driven in a known manner (not shown) from the carding machine through a wheel 5 and a clutch 6 mechanically engageable in a known manner and electrically disengageable. The feeding lattice 2 conveys the wool in the known manner from a hopper feeder (not completely shown on the left of the drawing) to a scale 'I suspended from a balance beam 8 which is provided with a counterweight 9 balancing the Weight of the scale. The bottom of the scale 1 is in the known manner formed of two doors I0 which can be swung down by the release of a latch II electrically, whereas the doors may be closed again mechanically in the conventional manner. When opening the doors ID of the scale I the wool batch weighed out therein is deposited on a feeding cloth I2 passing over a pulley I3 and extending to the carding machine proper (not shown in the drawing). The pulley I3 is driven in a known manner from the carding machine at a speed which is directly proportional to the speed of the carding means of the machine. On the shaft I 4 of the pulley I3 there is fixed a pulley I5 driving another pulley H by means of a belt IS. The pulley I! may be inter connected with a crank I8 by means of a single revolution clutch I9 which can be of any known construction and is electrically engageable.

Every time when the single revolution clutch i9 is engaged by an electric impulse, the crank I8 will thus effect one revolution and then remain at rest until the single revolution clutch I 9 is again engaged by means of a new impulse. The crank 18 is connected by means of a connecting rod 20 to the one arm 2I of a bell crank lever,

the other arm 22 of which is provided with a slot 23 in which a E i slides. The pin 2a is guided in a groove provided in the side wall of the feeding apparatus and parallel to the upper run of the feeding cloth i2, and is attached to a vertical plate 25 extending transversely over the feeding cloth 2. The bell crank lever 21, 22 is attached to a rotatably mounted shaft 2? extending under the feeding cloth l2 to the opposite side of :the. feeding apparatus iwhere a correspondingbelicrank'lever is arranged for operating a pin 24 on-the other end of the plate 25, which pin is guided in a corresponding manner: in a groove 25. Thus, when the crank i5 is rotated through one revolution;the-plateiii-will be reciprocated in a working cycleirrthe'groove' 25 from the position shown by means or dotted lines to the position 25 shown by 1116311930?" dashed. and dotted lines and back, a wool batch emptied from the scale i on to the feedingcloth" I 2 being moved to the right by the plate it which is travelling faster than the feeding cloth i2 and which packs the said batch together with the continuous wool layer 28 formed by wool batches already weighed out and deposited on the feeding clcithalfi;

The scale: 1 is connected by 1 means. of ia wire 2 9 on the like. to aweighingimechanismtiii having a hand 3t travelling oversea-graduation 32. The weighing:lrnechanismixis constructed in: such a way thatithe graduationxSZ is linear,v e. from th'ezero point 32; 'theihandiii 1' makes along the graduation a deflection which isv directly proportionalctorthe weight "of the wool innthe scale. 'i.

On an arbitrary point of the graduation 32 "an index= el 'may be fixedfor determining the desired weight of levery wool batch; The. index. 331sprovide'd with one or more electric; circuit con:- trolling means connected'by meansofa conductor Mao-the clutch t which is,.:besides connectecl to. one :poletof an electricpower source 35 :by means of a conductor 35.. The weight controlled means or hand 3 i has 011901.11'1018 electric "circuit cone trolling means 37. which? are -1 connected to the.

othrpolew of the: power 2 source 36 -;by .means .101?

a conductortil. When the hand: 3| reaches a. position opposite the index 133 Scluring the weigh-as ing-out of a wool-batch, the circuit controlling means'ofthe index 33 and the circuit controlling means -3'i 'cf lithe hand 3|?will1close ,a circuit through the clutchfi via therconductors 3t; 38, so that drive connection :betweenthe- WheeL'Slan-d the feeding .latti'ce .2 is:broken,: whereby thesupply of woolzto -the. scale? ceases: After soineloscillation the hand 3! will .stopinca position of::balance corresponding: to the real i weight of the wool batchtin thescale T, and this position of..the-hand: will ortenzliei-outg of line with? the index :33 (a. certain: overweight 'or the r Wool: batchin the scale iszindicated-in the :drawingl'.

Coaxial with'the hand}; !i is mountedsa'ratchet wheel 39 which'is constantly:rotated at a speed which-is directly proportional: to. the-speedoi the carding means rot :the machine and thus to the sspeed of the feeding cloth-"l2; Iii-the drawingsthedrive of. theratc-het'wheel 39 is shown by way'of example as comprising a sprocket HH secured to "ihBWVhGElAE :andidriving a chain 192 engagingasprocket: 33 .on :theinput shaft of a wormfirivel M the output shaft'of which carries a worni iile engaging:aawomnwheel 11% .whiclr is secured to the ratchet wheel 39.1. Coaxial with the 'handtl and lthe ratchet-. wheel- 39 is also:

- ductor i3;:solenoid.4d,w conductor;AE-ftimexswitch circuit controlling means 51 for cooperation with one or more electric circuit controlling means 42 on the hand 3 i. The circuit controlling means 42 of the hand is connected to the conductor 38, whereas the circuit controlling means of the feeler 49 is connected by means of a conductor 43 to a solenoid 56 mounted on the feeler and in turn connected by means of a conductor 55 to a time switch lie which is connected to the latchv H thescale bymea-ns of; a conductor 41-. From the latch ll vrhich maygbeaoi any known and suitable construction a conductor 45 leads to the single revolution clutch It which is connected by means of a conductor 49 to the same ,pole'of the-power source 3% as the conductoriiiii Omth'efe'eler 50 there is mounted a pawl Edor" such a known construction which, by snappingaover'aadead center, is able to occupy two positions only, viz. one in which it engages the ratchet wheelfieyand the other, in which it is out ofi engagement with the said ratchet wheel.

Wheniengaged by the pawl during a weighing operation, the ratchet wheel 35 which is driverrat a certain speed will thus slowly rotate the feeler Z-D in the same-"direction and in substantially 'the same pathras. the. hand-3 l which travelsltowards -increasing:weight. The feeler'f' lfi reachesl the hand 53! when: the latter hass stopped after. the supply -OfIiVOO1iQlZO'I1JhE ESCEl l lies-been cut or? in the manner describedabova;

Ther bythe -circuitis controlling-.;means. I: and-"1 lZ-ofthefeeIer anciithe hand close aicircuit from th'eone-poleof the power source SE'thliOUgh cone du'cton 38,: the circuit :controlling means, cone iirgconduit ll, latch 1 l- ,1concluit'58,-tsing1e revolu tion" clutchssi S and i? conductor fiito the other? pole: of-.-the;power.:source; Onnaccount thereof the ironr armature 0f the solenoid it, connected:

totth'e pawl 5fimOVSil3hE sai'drpawl tozthe posi-- tion in which-zit isnoutioi" engagement with the:- ratchet wheel 39,1 so: that the feeler ii] .iaswung: by the. actionohareturnaspring (not shown) back to 'the' aero point. 32'; oith'e graduation 32,- where -a sto'p inot hown) again swings the pawl 58 into'r engagement with the ratchet 'wheel *395 so a that theieeleiwstarts aanew swinginggcyclea At: the samwtime the latch'i i is given a current impulse so-that theidoors It are opened'and the-:7 woolbatch weighed. out in'the scale I is deposited on the feeding :cloth'12. Simultaneously there-- with 'zthe single trevolutionrclutch; l9 isgiven; current: impulse so:that it is engaged and rotates theicrankflfi through one revolution, the plate 2fi-efie'cting'a Working cycle in the manner-pro viously'idescrihed-and incorporating the deposited wool batchf'with the woollayer 28 on the-feeding cloth At. the :beginning ;ofthe --working 7; cycle ofrithe plateiethe doors lfi of the S9518??? :inechanically closed in r a known manner.

When the"v scale I is-vemptied the hand 3|- naturally;swings back tothe zero point. 32' of the-- graduation "32,; and almost immediately a-r-newweighingoperaticn is started, since the clutch.

:6 aisia'mechanically engaged in a known manner.-

for; taking 1up=,;the wool supply again to the scale. I b t-means oflthe feeding latticezr Immediately atcthe beginningsoi the weighing operation... the circuitcontrolling means Al -and.l52 of the feeler oonnect'the conductors :38 and 43 and it is there-v fore necessary toapreventt a .too early impulse to. solenoid 44, latch H, and "clutch i9. Thisrislr realized,by-pmeanssofthe time, switch .56 which mounted a feeler liii havingone:onmoreelectric'75einnaiknown-manner :holds the circuit between,

the conductors 45 and 41 broken during a certain time after the preceding current impulse. It will readily be seen that by means of the device described it is attained that per unit of length of the feeding cloth l2 the wool layer 28 will always contain. the same amount of wool by weight, since the wool layer 28 between two succeeding weighing operations is always moved by the feeding cloth through a distance from the turning point 28' of the plate 25 that is directly proportional to the weight of the following wool batch. The ratchet wheel 39 moves the feeler 40 at a speed directly proportional to the speed of the feeding cloth l2, so that the wool layer 28 will consequently move a greater dis tance when the hand 3| stops in a position corresponding to a higher weight of the wool batch than when it stops in a position corresponding to a lower weight of wool batch.

The principle of invention consists in bringing the scale to empty its contents on to the feeding cloth at intervals of such a length that the distance through which the feeding cloth is moved during each interval, is directly proportional to the real weight of the wool batch weighed out during the respective interval, and in causing the plate 26 to effect its working cycles in step with the emptyings of the scale, and it will readily be seen by those skilled in the art that the invention may be realized in other ways than that illustrated and described. As regards the device shown it should be pointed out that the circuit controlling means 33, 31, 4|, 42 may be constructed in any suitable manner.

What I claim and desire to secure by Letters Patent is:

1. In feeders for carding machines, in which successive batches of carding material are weighed out with errors that vary in relation to the desired weight, in a scale emptying the batches weighed out in succession on to a feeding belt which conveys the carding material to the carding machine proper and travels at a determined speed relative to the speed of the carding machine, the successive batches from the scale being packed together in a continuous layer by means of a plate reciprocating longitudinally of the said feeding belt, a device comprising weight controlled means connected to said scale and movable by said scale along a predetermined path directly proportional to the real amount by weight of carding material in said scale, electric circuit controlling means on said weight controlled means, feeler means, means for driving said feeler means at a speed which is directly proportional to that of the carding machine and thus to that of the feeding belt, in substantially the same path and the same direction as said weight controlled means, electric circuit controlling means on said feeler means, an electrically operable device for emptying said scale, an electrically operable device for effecting operation of said plate packing the carding material together on said feeding belt, an electric power source, and electric circuit means connecting said devices with said circuit controlling means and said power source, said circuit controlling means on said weight controlled means and on said feeler means being adapted, when said weight controlled means and said feeler means meet in their path of motion, to alter the condition of said electric circuit means in order to obtain an impulse causing operation of said electrically operable devices.

2. A feeder for a carding machine comprising a conveyor, means for operating the conveyor at a predetermined speed for conveying material to the carding machine, a material weighing machine having a pan provided with discharge mechanism and positioned above the conveyor to discharge material onto the conveyor, a first element actuated by the weighing machin and moved in a predetermined path through a distance proportional to the weight of material in the pan to a position of rest, a second element movable in a path following that of the first element, means moving the second element at a rate proportional to the speed of the conveyor, and means operable upon the second movable element reaching the first movable element for actuating the discharge mechanism of the pan to discharge material from the pan onto the conveyor.

3. A feeder for a carding machine comprising a conveyor, means for operating the conveyor at a predetermined speed for conveying material to the carding machine, a material weighing machine having a pan provided with discharge mechanism and positioned above the conveyor to discharge material onto the conveyor, a first element actuated by the weighing machine and moved in a predetermined path through a dis tance proportional to the weight of material in the pan to a position of rest, a second element movable in a path following that of the first element, means for moving the second element at a rate proportional to the speed of the conveyor, electrical contacts carried by said movable elements, an electric actuator for the pan discharge mechanism, and an electric circuit 00- operating with said contacts and pan discharge mechanism actuator for energizing said actuator upon engagement of said contacts.

4. A method of feeding carding material to a carding machine comprising moving a conveyor at a predetermined speed to convey carding material to the carding machine, cyclically feeding carding material to a scale pan, terminating the feeding of the material to the pan when an approximate predetermined weight of material has been introduced into the pan, discharging the weighed contents of the pan onto the conveyor, and varying the interval between the discharging steps of successive cycles directly with the weight of material to be discharged at the end of the interval.

5. A method of feeding carding material to a carding machine comprising moving a conveyor at a predetermined speed to convey carding material to the carding machine, cyclically feeding carding material to a scale pan, terminating the feeding of the material to the pan when an ap proximate predetermined weight of material has been introduced into the pan, discharging the weighed contents of the pan onto the conveyor, and varying the interval between the discharging steps of successive cycles directly with the weight of material to be discharged at the end of the interval, during each cycle moving the material deposited on the conveyor forwardly to unite it with previously deposited material, and varying the interval between the moving step of successive cycles to correspond to the interval betwen said discharging steps.

6. A feeder for a carding machine comprising a conveyor, means for operating the conveyor at a predetermined speed for conveying material to the carding machine, a weighing scale pan, means for feeding material to the scale pan, means actuated by the scale pan for producing ofthe-first efiect and dischargetmeans on the m scale pan actuated by: the .control. means for. dis.-- charging; material weighed. on..the scalepan, from the. scale -pan ontovthe conveyor.

References; :Cited. in .the 111e, of this patent UNETEB QSTATESEIPATEN'TS Number.

N amei Date Howe- Oct. 31; 1922 Schimek Nov. 6,1923 A1'1en- Mar. 31, 193-1 Ev'oy Nov. 12, 1940' Thomas etal. Apr. 15, 1947- Curion'r; Apr; 5,1949 

